The air concentrations of NOx related to tobacco smoke; a systematic review

Background: Environmental tobacco smoke (ETS) or the second hand smoke, similar to the firsthand smoke, is a complex mixture containing thousands of chemicals which many of them areknown as carcinogens. In this regard, ETS is classified as human carcinogen. High combustiontemperature of tobacco and presence of nitrogen in the tobacco can lead to the release of nitrogenoxides (NOX). Between the NOx, NO۲ irritates the respiratory system and can damage its cellssuch as the mucous membranes of lungs. Inhalation of high levels of nitrogen oxides can causeirritation, spasm and tissue inflammation in the throat and upper respiratory tract, decrease inoxygen supply to body tissues, accumulation of fluid in the lungs and death. We raised this studyto review the reports about the exposure to NOx related to tobacco smoke to evaluate the probablehealth effects.Method: The present systematic review study was carried out by searching in the period of ۱۸thof December to ۱۱th of November in the data bases of Science direct, Springer, Pubmed andGoogle scholar among the articles in English language. The keywords of the search plan includednitrogen oxide, NOX, ETS, Cigarette smoke, Waterpipe smoke, and tobacco smoke. ۷۹۷ articleswere found and reviewed. Finally ۷ articles met the above study criteria. Then, the concentrationof nitrogen oxides and the study conditions including the sampling location and the environmentwere considered in the results.Results: The obtained results show that the man tobacco smoke related concentration of NOX inambient air was ۹.۷۱±۱۱.۰۳ ppm, which is higher than the annual guideline level of free air quality(۰.۰۵۳ ppm). According to these results, the mean concentration of NOX in cigarette smoke was۳۲۹.۴۵±۴۶۵.۴۳ ppm, which is higher than the guideline level. The mean concentration of NOX inthe smoking areas where higher than the non-smoking areas (۱۷.۸۰ vs. ۱۲.۴۷ ppm). Given theresults, the mean concentration of NOX in cigarette smoke was ۵.۶۶ ppm and it was ۰.۱۶ ppm inhookah smoke. Also, the concentration of NO in the upstream cigarette smoke was higher thanNO۲.Conclusion: According to the obtained results, tobacco smoking is effective on the concentrationof NOx in the smoking environments. The cigarette is more suspected to emission of NOxcompared to watepipe and the tobacco smoking can expose the people with high levels of NOxregarding the limited guideline levels.

کلیدواژه ها:

Air Pollution ، Cigarette ، Waterpipe ، Nitrogen Oxides